<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Form</title>
</head>

<body>
    <section>
        <label for="user_name">用户名：</label>
        <input type="text" id="user_name" name="user_name">
        <p>请输入用户名</p>
    </section>

</body>

</html>